1. Field of the Invention
This invention pertains to door and track assemblies for cargo-carrying trailers of the type having vertically slidable side access doors.
2. Background of the Prior Art
The prior art shows tracks or guideways for slidable members which ride on various types of bearing surfaces. The difficulty with tracks for vertically sliding doors is that the tracks do not provide durable long lasting smooth surfaces for door rollers. Rather, the prior art tracks for such doors were inadequate in that they caused early wear on door rollers such that the doors needed to be removed and rollers replaced. This was time consuming and expensive and caused considerable downtime in the use of such trailers. Representative of the prior art patents showing tracks for slidable devices are listed below. Copies are furnished for the record.
______________________________________ Inventor Patent No. ______________________________________ E. T. Larkin 2,022,917 J. Daugherty 2,675,276 W. B. Conrad 2,835,539 J. C. Evans 3,054,645 Sahm 3,813,132 Mellor 3,885,837 ______________________________________